<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
</head>
<body>
    <div id="app">
        <!-- 常量、变量、表达式、函数 -->
        {{ "msg" }}                 <br>         
        {{ msg }}                   <br>
        {{ 1>2?msg:msg1 }}          <br>
        {{ msg+msg1 }}              <br>
        {{ msg.toUpperCase() }}
    </div>

    <script>
        let vm = new Vue({
            el: '#app',
            data: {
                msg: 'Hello Vue',
                msg1: 'Hello World'
            } 
        })

    </script>
</body>
</html>